Table 1. Demographic characteristics of patients and association between potential risk factors and childhood acute leukemia. a: odds ratio, b: confidence interval, c: acute lymphoblastic leukemia, d: acute myeloid leukemia, e: ≥2 drinks per week, f: Chi-square test was not applicable due to the small number of mothers who consumed alcohol during pregnancy, g: ≥1 cigarette per week for ≥6 month.
| Variables | Cases (N=108) | Controls (N=108) | Crude ORa [95% CIb] | ||
|---|---|---|---|---|---|
| N | % | N | % | ||
| Type of leukemia | |||||
| ALLc | 93 | 86.1 | |||
| AMLd | 9 | 8.3 | |||
| Gender: Male | 63 | 58.3 | |||
| Ethnicity: Greek | 94 | 87.0 | |||
| Age at diagnosis: 2-6 years old | 64 | 59.3 | |||
| Family history of cancer | 52 | 48.1 | 37 | 34.3 | 1.85 [1.07-3,20] |
| Birth weight: ≥ 3500g | 47 | 43.5 | 29 | 26.9 | 2.27 [1.27-4.04] |
| Residence in an urban area (≥2.000 residents) |
79 | 73.1 | 82 | 75.9 | 0.86 [0.47-1.59] |
| Ever-attendance of day care | 48 | 44.4 | 52 | 48.1 | 0.86 [0.50-1.47] |
| Paternal age at birth: >35 years | 37 | 34.3 | 41 | 38.0 | 0.85 [0.49-1.49] |
| Maternal age at birth: >35 years | 19 | 17.6 | 24 | 22.2 | 0.75 [0.38-1.46] |
| Paternal educational level: >9 years | 67 | 62.0 | 66 | 61.1 | 1.04 [0.60-1.80] |
| Maternal educational level: >9 years | 78 | 72.2 | 74 | 68.5 | 1.20 [0.67-2.14] |
| Maternal medication use during pregnancy | 21 | 19.4 | 37 | 34.3 | 0.46 [0.25-0.86] |
| Paternal alcohol consumptione 1 year before conception | 64 | 59.3 | 51 | 47.2 | 1.63 [0.95-2.79] |
| Paternal alcohol consumptione during pregnancy | 64 | 59.3 | 50 | 46.3 | 1.69 [0.98-2.89] |
| Maternal alcohol consumptione 1 year before conception | 19 | 17.6 | 19 | 17.6 | 1.00 [0.50-2.02] |
| Maternal alcohol consumptione during pregnancy | 2 | 1.9 | 4 | 3.7 | - f |
| Paternal smokingg 1 year before conception | 63 | 58.3 | 60 | 55.6 | 1.12 [0.65-1.92] |
| Paternal smokingg during pregnancy | 59 | 54.6 | 57 | 52.8 | 1.08 [0.63-1.84] |
| Paternal smokingg after pregnancy | 57 | 52.8 | 52 | 48.1 | 1.20 [0.71-2.05] |
| Maternal smokingg 1 year before conception | 43 | 39.8 | 43 | 39.8 | 1.00 [0.58-1.72] |
| Maternal smokingg during pregnancy | 14 | 13.0 | 22 | 20.4 | 0.58 [0.28-1.21] |
| Maternal smokingg after pregnancy | 9 | 8.3 | 7 | 6.5 | 1.31 [0.47-3.66] |
| Paternal agricultural activities | 25 | 23.1 | 26 | 24.1 | 0.95 [0.51-1.78] |
| Maternal agricultural activities | 9 | 8.3 | 11 | 10.2 | 0.80 [0.32-2.02] |